The present invention is directed to a rail vehicle for transporting heavy leads, particularly for carrying metallurgical vessels. The heavy loads are supported on a vehicle frame and the vehicle frame, itself, is supported on rails by either two pairs of wheels or on a plurality of wheel groupings.
A rail vehicle of this type serves to transport heavy loads on rails. Since the weight forces are so very great, the travel speed is, in contrast to that of other rail vehicles, of secondary significance. The focus of the present invention is, therefore, on rail vehicles capable of use in foundry operations, i.e., those which are used to transport metallurgical converters and steelmaking furnaces, including so-called vessel changing vehicles and casting ladles.
Experience has shown that rail vehicles are sometimes, in order to avoid high cost, constructed without suspension-type spring action. So constructed, the vehicles, if operated on uneven rail tracks, exhibit great wear and tear on both the rails and the wheel support structure.
The rail tracks in the foundries, because of the changed technology in steel production and steel refining, have in the last few years been considerably extended in length. On such extended rail tracks, more and more inaccuracies between the rail levels will inevitably occur. Weighted or loaded rail vehicles have, per se, a certain degree of elasticity of their own which, if travelling on uneven rails, often results in direct contact between the wheels and the rails. Nevertheless, the maintenance of the rail tracks has proved to be relatively expensive and difficult for heavy load traffic.
In foundries, for example, deviations between tracks from a standard level are at present 30 to 40 mm. With loads of 1200 t and more, a share of approximately 300 t acts upon each of the vehicles' four wheels (assuming an equal load distribution).
While the elastic carriage frames of the rail vehicles change their shape up to a few millimeters, this will not, however, occur to the extent of the 30 to 40 mm track level deviations. Consequently, because of the difference in track levels and the inability of the vehicle to fully accommodate the deviations, an equal load distribution over the four wheels or wheel groups will not precisely occur. On the other hand, it is not reasonable to construct the rail vehicle so that it is more pliant or elastic in order to effect an even greater deformation when loaded. Furthermore, track level deviations of the rail tracks must be taken into account when the rails slope in the counter-direction from the intended direction of travel when the vehicle is fully loaded.